1. Field of the Invention
The present invention relates to a battery cooling apparatus for controlling the temperature of a battery mounted on an automotive vehicle.
2. Description of the Related Art
In a conventional battery cooling apparatus for cooling an in-vehicle battery, air in a compartment of the vehicle is blown against the battery to cool the battery (Japanese Unexamined Patent Publication No. 10-252467).
A battery for supplying power to a driving motor of an electric car or a hybrid car is mounted normally in the neighborhood of a rear seat in the rear part of a vehicle body. Therefore, an air inlet for a battery cooling apparatus is also arranged in the rear part of the vehicle body such as under the rear seat, or a rear tray (or a trunk space) as described in the publication cited above.
The temperature of air blown into the compartment of the vehicle from an air conditioner, on the other hand, though dependent on air-conditioning parameters, such as a set temperature and an internal air temperature, is normally controlled at about 25° C. In the case where the air inlet of the battery cooling apparatus is arranged in the rear part of the vehicle body under the rear seat or the rear tray, for example, the temperature of air sucked into the air inlet rises to as high as about 30° C. to 31° C. due to disturbances such as the heat of an exhaust pipe and sunlight.
It is, therefore, difficult to cool the battery sufficiently and, in order to secure a sufficient cooling ability, the flow rate of air supplied to the battery is required to be increased, thereby leading to the problems of increased noise of air flow and shorter service life of a blower.
Also, an increased heat radiation area, i.e. an increased surface area of the battery to secure a sufficient cooling capacity would increase both size and production cost of the battery.